buffer: remove unreachable overflow check in atob

haramj · richardlau · commit a483bfd3f0dc · 2026-07-06T12:30:27.000Z
Signed-off-by: haramjeong <04harams77@gmail.com> PR-URL: #60161 Reviewed-By: René <contact.9a5d6388@renegade334.me.uk> Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com> Reviewed-By: Gürgün Dayıoğlu <hey@gurgun.day> Reviewed-By: James M Snell <jasnell@gmail.com>
diff --git a/lib/buffer.js b/lib/buffer.js
@@ -110,6 +110,8 @@ const {
   inspect: utilInspect,
 } = require('internal/util/inspect');
 
+const assert = require('internal/assert');
+
 const {
   codes: {
     ERR_BUFFER_OUT_OF_BOUNDS,
@@ -1401,9 +1403,9 @@ function atob(input) {
       throw lazyDOMException(
         'The string to be decoded is not correctly encoded.',
         'InvalidCharacterError');
-    case -3: // Possible overflow
-      // TODO(@anonrig): Throw correct error in here.
-      throw lazyDOMException('The input causes overflow.', 'InvalidCharacterError');
+    case -3:
+      assert.fail('Unrecognized simdutf error');
+      break;
     default:
       return result;
   }
diff --git a/src/node_buffer.cc b/src/node_buffer.cc
@@ -1512,7 +1512,7 @@ static void Btoa(const FunctionCallbackInfo<Value>& args) {
 // In case of error, a negative value is returned:
 // * -1 indicates a single character remained,
 // * -2 indicates an invalid character,
-// * -3 indicates a possible overflow (i.e., more than 2 GB output).
+// * -3 indicates an unrecognized simdutf error.
 static void Atob(const FunctionCallbackInfo<Value>& args) {
   CHECK_EQ(args.Length(), 1);
   Environment* env = Environment::GetCurrent(args);
@@ -1557,7 +1557,7 @@ static void Atob(const FunctionCallbackInfo<Value>& args) {
     return args.GetReturnValue().Set(value);
   }
 
-  // Default value is: "possible overflow"
+  // Default value is: "unrecognized simdutf error"
   int32_t error_code = -3;
 
   if (result.error == simdutf::error_code::INVALID_BASE64_CHARACTER) {
